In this paper, we have disussed the internal rotation in sulfonylurea molecules,which belong to high active and low toxic herbicides and take the form of conformational iso-mers in their crystal structures. In order t...In this paper, we have disussed the internal rotation in sulfonylurea molecules,which belong to high active and low toxic herbicides and take the form of conformational iso-mers in their crystal structures. In order to understand the formation of their enantimers, weobtained a series of data of molecular energy of different conformation by using the molecularmechanics method and the stepwise rotation single-bond method. We found out the lowestinternal rotation passage and obtained the energy barrier of hindered rotation which is less 60kJ/mol. This result shows that there is a lower energy passage to exchange the conforma-tional isomers of these molecules, so exchanging the different conformational isomers is notvery difficult.展开更多
文摘In this paper, we have disussed the internal rotation in sulfonylurea molecules,which belong to high active and low toxic herbicides and take the form of conformational iso-mers in their crystal structures. In order to understand the formation of their enantimers, weobtained a series of data of molecular energy of different conformation by using the molecularmechanics method and the stepwise rotation single-bond method. We found out the lowestinternal rotation passage and obtained the energy barrier of hindered rotation which is less 60kJ/mol. This result shows that there is a lower energy passage to exchange the conforma-tional isomers of these molecules, so exchanging the different conformational isomers is notvery difficult.
